Performance and control of the MMT thermal system

ACKNOWLEDGMENTSWe would like to acknowledge the great effort of the MMT operators, A. Milone, J. McAfee, and M. Alegria.Without their tireless attention and input this paper would not have been possible. We also thank S. West forvaluable comments and C. Wainright for his help in providing some mechanical details.REFERENCES1. D. Blanco, M. Alegria, S. Callahan, D. Clark, B. Comisso, C. B. Foltz, J. D. Gibson, C. Heller, R. James,B. Kindred, S. King, C. Knop, H. Lester, J. McAfee, A. Milone, R. Ortiz, T. Pickering, P. Ritz, B. Russ,B. Schmidt, D. Smith, P. Spencer, T. Trebisky, K. Van Horn, C. Wainwright, S. C. West, G. Williams, andJ. T. Williams, “The new MMT,” in Proc. SPIE Vol. xxx, These proceedings., 2004.2. D. G. Fabricant, B. A. McLeod, and S. C. West, “Optical Specifications for the MMT Conversion,” MMTTechnical Report 35, MMTO, 1999.3. A. Y. S. Cheng and J. R. P. Angel, “Thermal Stabilization of Honeycomb Mirrors,” in Very Large Telescopesand their Instrumentation, ESO Conference and Workshop Proceedings, Proceedings of a ESO Conference onVery Large Telescopes and their Instrumentation, held in Garching, March 21-24, 1988, Garching: EuropeanSouthern Observatory (ESO), 1988, edited by Marie-Helene Ulrich., p.467, pp. 467–+, 1988.4. C. M. Lowne, “An investigation of the effects of mirror temperature upon telescope seeing,” MNRAS 188,pp. 249–259, July 1979.5. L. Miglietta, “Air-Air Ejector for Large Mirrors Temperature Control: Numerical Simulations and ExperimentalData,” in Progress in Telescope and Instrumentation Technologies, pp. 361–+, 1992.6. P. Benjamin and S. Callahan, “6.5-m Ventilation System: Exhaust Ejector Performance Test Results,”MMT Conversion Technical Memorandum 97-1, MMTO, 1997.7. S. C. West, S. Callahan, F. H. Chaffee, W. B. Davison, S. T. Derigne, D. G. Fabricant, C. B. Foltz, J. M.Hill, R. H. Nagel, A. D. Poyner, and J. T. Williams, “Toward first light for the 6.5-m MMT Telescope,”in Proc. SPIE Vol. 2871, p. 38-48, Optical Telescopes of Today and Tomorrow, Arne L. Ardeberg; Ed.,pp. 38–48, Mar. 1997.8. S. C. West, P. Spencer, and S. Callahan, “A high-precision diffferential-thermocouple temperature measurementsystem for the 6.5m MMT primary mirror,” MMT Conversion Technical Memorandum 99-2, MMTO,1999.9. J. D. Gibson, “Evaluation of Thermal Performance for the MMT Primary Mirror During January 2003,”MMT Technical Memorandum 03-7, MMTO, 2003.10. R. Racine, D. Salmon, D. Cowley, and J. Sovka, “Mirror, dome, and natural seeing at CFHT,” PASP 103,pp. 1020–1032, Sept. 1991.11. L. Zago, The Effect of the Local Atmospheric Environment on Astronomical Observations. PhD thesis, EcolePolytechnique Federal de Lausanne, 1995. Thesis No. 1394.12. L. Zago, “Engineering handbook for local and dome seeing,” in Proc. SPIE Vol. 2871, p. 726-736, OpticalTelescopes of Today and Tomorrow, Arne L. Ardeberg; Ed., pp. 726–736, Mar. 1997.13. T. E. Pickering, S. C. West, and D. G. Fabricant, “Active optics and wavefront sensing at the upgraded6.5-meter MMT,” in Proc. SPIE Vol. xxx, These proceedings., 2004.